1. Field of the Invention
The present invention relates to apparatus for cutting and separating sheets of accurate length from long lengths of sheet or web material and for stacking each sheet in a very accurate position relative to printed lines on the sheet and on an adjacent sheet on the stack of sheets.
Although the apparatus of the present invention has wide application it is particularly suited for cutting, separating and accurately stacking sheets of web material, such as paper or cloth, for example, or metal material such as aluminum, for example, in the preparation of forming an uniform cellular structure, for example, a honeycomb mass or block.
2. Prior Art
It is well known to form a uniform cellular structure or block, such as a honeycomb mass or block, by cutting sheets from a continuous web on which has previously been applied, adhesive, cement or glue stripes, in a precise predetermined pattern across one surface of the web and stacking the sheets one on top of the other. The stack of sheets with the adhesive stripes on a common surface are subjected to pressure and heat to activate and/or cure the adhesive so that each sheet becomes adhered to its adjacent sheet in a particular pattern so that the sheets, when separated, form a cellular block with each cell of the structure the same shape and size.
U.S. Pat. No. 4,301,700 issued Nov. 24, 1881 discloses a cutting apparatus suited particularly for cutting sheets of very accurate length from a long, continuous supply of web, metal or other material generally used for preparing stacks of sheets used in making cellular blocks.
It has been found that in the manmaking honeycomb process, accuracy and uniformity in the spacing and width of the adhesive or cement stripes or lines set down on surface of the web or metal material used, the cutting to length and stacking of the cut sheets and the positioning of each sheet relative to its adjacent sheet are extremely important for the generation of a block of a man-made honeycomb, with uniform cells.
The adhesive, glue or cement stripes or lines may be applied to a long sheet or web across its width, i.e., perpendicular to the length of the web. The adhesive may be an epoxy, applied to the web in a liquid form using, for example, a printer. After the adhesive lines are printed across the web, the adhesive material printed on the web is dried so as to make the adhesive dormant.
State of the art printers print adhesive lines in a sharply defined pattern, relative to width of adhesive line, the spacing between adhesive lines and repetition of the pattern along the web or other material.
The width of the adhesive lines and the spacing between lines is a function of the size of the cell in the honeycomb mass to be manufactured. For example a honeycomb block made up from 1/8 inch cells may be generated by using adhesive stripes or lines 0.070 inches wide with a spacing of 0.280 inches between adhesive stripes or lines.
U.S. Pat. No. 4,301,700 teaches apparatus for cutting a continuous web into sheets of the same predetermined length, repetitively, by feeding the a continuous material on to an aligning table which aligns the continuous material without subjecting the material to a tension which may injure the adhesive stripes on the material. The continuous material is held flattened and stiffened at or near the termination point of the material. The continuous material or web may then be sheared or cut across its width by a conventional cutter to form a termination of the material.